Can't render with Displacement Modifier on - is it destroying the mesh?
I'll bet you have a duplicate of the loop from before the displacement modifier was applied rendering at the same time. Disabling the eye icon in the Collections panel doesn't stop rendering. Click on that funnel-looking-thing to enable more filtering options. You want the one for rendering, which looks like a camera. Disable that for the duplicate. You can also do that in the "Object" panel (orange square-shaped tab)

EDIT: Yep. Turn off that camera icon: